The aerosol impact spectrometer: a versatile platform for studying the velocity dependence of nanoparticle-surface impact phenomena

• Published in: EPJ techniques and instrumentation Vol. 4; no. 1; pp. 1 - 17
• Main Authors: Adamson, Brian D., Miller, Morgan E. C., Continetti, Robert E.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 11.04.2017; Springer Nature B.V; SpringerOpen
• Subjects: Atomic; Biological and Medical Physics; Biomaterials; Biophysics; Characterization and Evaluation of Materials; Coefficient of restitution; Deceleration; Digitization; Image charge; Image charge detection; Image detection; Ionization; Ions; Latex; Measurement Science and Instrumentation; Molecular; Nanoparticle acceleration; Nanoparticles; Optical and Plasma Physics; Physics; Physics and Astronomy; Polystyrene resins; Research Article; Silicon; Spectroscopy and Microscopy; Image charge detection; Nanoparticle acceleration; Deceleration; Coefficient of restitution
• ISSN: 2195-7045; 2195-7045
• DOI: 10.1140/epjti/s40485-017-0037-6

A new apparatus designed to accelerate/decelerate and study the surface impact phenomena of charged aerosols and nanoparticles over a wide range of mass-to-charge ( m/z ) ratios and final velocities is described. A nanoparticle ion source coupled with a linear electrostatic trap configured as an image charge detection (ICD) mass spectrometer allows determination of the mass-to-charge ratio and the absolute charge and mass of single nanoparticles. A nine-stage linear accelerator/decelerator is used to fix the final velocity of the nanoparticles, and in the results reported here the coefficient of restitution for polystyrene latex spheres (PSLs) impacting on silicon is measured using ICD techniques. To enable this apparatus to study a wide range of m/z , the data acquisition system uses a transient digitizer interfaced to a field-programmable gate array module that allows real time calculation of m/z and determination of the pulse sequence for the linear accelerator/decelerator. Electrospray ionization of a colloidal suspension of PSL spheres of 510 and 990 nm has been used to demonstrate acceleration and deceleration of charged nanoparticles and the resolution of the apparatus. Measurements of the coefficient of restitution for PSLs on silicon over the range 10-400 m/s are consistent with previous studies.